A fellow Mainer!! Great project and looks like good progress has been had so far! I hope the STI block is in good shape so you don't have any surprises later on that would have been better addressed during the swap. I WRX-swapped my 06 2.5i at my dad's house in Bangor in March/April. One thing that held me up was tracking down the third fuel line needed for the turbo fuel rails/manifold. I forget if the the additional line is a return or a vent. I was most nervous about swapping the wiring harnesses but it wasn't too bad taking my time getting plugs and clips undone so as not to mangle them.
Sad to see that STI as rusty as it is but glad you'll be giving it another chance at life!